Shortly after updating from Windows 8 to 8.1 on a new PC already running Windows 8, I started getting "<my email name>@outlook.com unavailable" displayed in the top line of the Calendar, People and Mail apps during attempted syncs. And my Windows 8 Calendar and People apps no longer syncs with what is in outlook.com.

I was previously syncing with my outlook.com account with no issues. Running outlook.com from my Internet browser works fine and mail, calendar and people functions are working well. My Ipod Touch also syncs ok with outlook.com, both directions, for the Contacts and Calendar functions.

Tried removing the account from Windows 8, re-implementing to no avail.

I'm at a loss why this started happening after the upgrade. Anyone else experiencing a similar issue? Right now, my Calendar and People apps are dead in the water, so I've reverted to using Outlook.com on web to manage my Email, Calendar and People (contacts).